Composite Application Framework - Store Passwords?

We are investigating real-world use cases for the Composite Application Framework (CAF) feature.  This feature works great when the user does not need to authenticate (or auto authentication is turned on).  The problem lies when the user needs to log into the site that they are trying to link to (GENERICURL).  Is there a way to store the credentials of the site in JDE so that the CAF URL automatically authenticates?  That would be awesome!

I notice that CAF can be used to consume data from web services.  This is used to integrate with Oracle's BI solution.  Is there a way of doing this generically for any web service?  That would be very useful to allow users to quickly integrate with external systems.